661453 has 16 divisors (see below), whose sum is σ = 783216. Its totient is φ = 552960.

The previous prime is 661439. The next prime is 661459. The reversal of 661453 is 354166.

It can be written as a sum of positive squares in 8 ways, for example, as 56169 + 605284 = 237^2 + 778^2 .

It is a cyclic number.

It is not a de Polignac number, because 661453 - 2⁵ = 661421 is a prime.

It is a Duffinian number.

Its product of digits (2160) is a multiple of the sum of its prime divisors (144).

661453 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9025 + ... + 9097.

It is an arithmetic number, because the mean of its divisors is an integer number (48951).

2⁶⁶¹⁴⁵³ is an apocalyptic number.

It is an amenable number.

661453 is a deficient number, since it is larger than the sum of its proper divisors (121763).

661453 is a wasteful number, since it uses less digits than its factorization.

661453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144.

The product of its digits is 2160, while the sum is 25.

The square root of 661453 is about 813.2976085050. The cubic root of 661453 is about 87.1297223648.

The spelling of 661453 in words is "six hundred sixty-one thousand, four hundred fifty-three".